The present invention relates generally to equipment utilized in conjunction with operations performed in subterranean wells, and more particularly to surface feature improvements to a downhole fluid flow control device operable to control the inflow and outflow of injection fluids.
In certain subterranean formations, fluid is injected into the reservoir to displace or sweep the hydrocarbons out of the reservoir. This method of stimulating production is sometimes referred to as a method of “Enhanced Oil Recovery” and may be called water flooding, gas flooding, steam injection, etc. For the purpose of this specification, the general process will be defined as injecting a fluid (gas or liquid) into a reservoir in order to displace, drive, or increase the production of the existing hydrocarbons into a producing well.
Without limiting the scope of the disclosure, its background will be described with reference to steam injection into a hydrocarbon bearing subterranean formation, as an example. In wells having multiple zones, due to differences in the pressure and/or permeability of the zones as well as pressure and thermal losses in the tubular string, the amount of steam entering each zone may be difficult to control. One way to assure the desired steam injection at each zone is to establish a critical flow regime through nozzles or orifices associated with each zone. The number and size of the orifices may be varied in order to control the injection of steam. For example, smaller orifice sizes result in reduced flow area, which ultimately reduces the flow rate of steam through the orifice.
Injecting steam into a downhole tubular often results in a combination of fluids (i.e., vapor and water condensate) developing in the interior of the downhole tubular. The vapor and water travel down the inner diameter (“ID”) of the downhole tubular without any particular pattern. Some of the fluids are blown out through the orifices, but most flow past the orifices to the bottom of the wellbore, where the water condensate tends to collect, resulting in a high vapor content injection uphole and a low vapor injection content downhole. Further, without any particular guidance for the fluids through the orifices, the large amounts of condensate flowing to the bottom of the wellbore may damage the lowest zone of production.
While embodiments of this disclosure have been depicted and described and are defined by reference to exemplary embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and are not exhaustive of the scope of the disclosure.